The present invention relates generally to an optical demultiplexer. More particularly, the invention relates an optical demultiplexer which comprises an angular dispersion generator and an angular dispersion amplifier. Such optical demultiplexer provides a basis for robust designs of multi-channel optical communication receiver, spectrum analyzer, switch and router.
Signal multiplexing is a very important function in optical communication. To increase the system bandwidth, it is common to propagate a number of channels with different optical characteristics over the same carrier such as an optical fiber or a waveguide. The channel multiplexed in the signal are then separated to be routed into individual destinations. Currently, the commonly applied multiplexing technique includes multiplexing various wavelength channels as one signal to be transmitted over a carrier. The conventional dense wavelength division multiplexing (DWDM) technologies are found to be based on: (1) thin-film dielectric devices; (2) diffraction gratings; (3) planar array waveguides; (4) fiber-based devices with Bragg gratings or interferometric structures; and (5) interleave technologies. The current technology limit is near 50 GHz.
Limitations in application of the multiplexing/demultiplexing conventional technologies include the difficulty in distinguishing the channels after being demultiplexed, signal loss during demultiplexing, temperature sensitivity that causes demultiplexing inaccuracy, and complexity in fabrication.